Changeant or opalescent glass



Patented Feb. 28, 1933 UNITED STATES PATENT OFFICE NORBEBT KRHDII, OFREITENDOERF A/TESS, GZECHOSLOVAKIA, ASSIGNOR TO FIRM GLASHUTTENWERKEVORM. J. SCHREIIBEB & NEFFENfOF REITENDORF ,A/TESS,

GZECHOSLOVAKIA CHANGEANT QR OPALESGEN '1 GLASS 11o Drawing. Applicationfiled July 30, 1930, Serial No. 471,894, and in Czechoslovakia August 8,1929.

This invention relates to a process for the manufacture of changeant oropalescent glass and to the product resulting therefrom. For

' this purpose fluorescent glass colours have been heretoforeexclusively used, such as in particular the oxides of uranium, neodymiumand praseodymium. The use of fluorescent glass colours is based upontheir dichroic properties. The lightpassing through is not coloured oronly feebly so, while the light reflected from its surface (fluorescentlight) is intensely coloured.

The present invention is based on the discovery that thechangeant-eflect is increased when a fluorescent glassthat is a glasscolored with fluorescent producing oxides or a glass layer so coloredisflashed or covered with one or more diflerently coloured, suitablyintensely coloured, glasses or layers of glass, or inversely when aglass ordinarily coloured in one or more layers is flashed or coveredwith one or more fluorescent glass layers of another colour. By thesemeans it is achieved that at all places with normal colour-subtraction,the flashor'cover-colour is practically exclusively visible, while atrefleeting or optic places, the fluorescent colour appears almostexclusively on account of this colour predominating.

Reflecting and optic places are all such places of the glass body whichstand out in the smooth or plane surface of the glass, such as forinstance depressions, cut or ground surfaces, projecting surfaces, ribsand the 3 like, further rims or optic edges, transition surfaces,penetration surfaces etc., as is mostly the case with hollow glassware,table glassware, solid glassware and the like.

Thus, for example, an uranium-green col- 4 oured so called optic glasscup which has been flashed or covered ruby-red shows a dullred colourwith a green rim of the cup,-green optic strips and reen ice (that meansthe lower portion 0 the cup-goblet adjacent-- 4 to the stem).

'changeant or opalescent efiect can be corv respondingly influenced.

Also a method of carrying out the invention can be made use of whichconsists in superimposing the flashed layers of glass in such a mannerthat they lie in the form of oppositely directed wedges one above theother or merge one into the other, so that the thickness of thesuperimposed layers varies in each cross-section, or differs at variousplaces, a concave or convex line of demarcation, thereby, giving thebest eflect.

With glasses comprising more than two layers also colourless layers ofglass can be made use of.

What-I claim is:

1. A changeant glass comprising a plurality of layers, at least one ofwhich is of a fluorescent light-transmitting glass and at least one ofwhich is a differently intensely colored, light-transmitting glass.

2. A changeant glass according to claim 1,

wherein the glass is optically heterogeneous.

3. A changeant glass according to claim 1, wherein the glass isoptically heterogeneous for different angles of vision.

4. A changeant glass comprising a plurality of layers, at least one ofwhich is of a fluorescent light-transmitting glass, at least one ofwhich is of a diflerently intensely colored light-transmitting glass,and one of which is colorless glass.

5. A changeant glass comprising a plurality of, layers, atleast one ofwhich is of a fluorescent transparent glass and at least one of which is'of a difl'erently intensely colored glass, the colors of the said glasslayers being such, that one layer is at least partially transparent tothe light rays transmitted by the other layer.

7 6. A changeant glass comgrisin a. plu-l rality of layers, at least oneo whic 'is of a fluorescent transparent glass and at least one.

of which is of a differently intensely colored glass, the colors of theglass layers being such that the outer layer is at least partiallytrans- Farent to the rays transmitted by the inner ayer.

In witness whereof I have hereunto signed 10 my name.

NORBERT KREIDL.

y as.

